Tactile-Pixels May Bring Advanced Touch-Sensitivity to Devices

Touchscreens are becoming a near ubiquitous technology with smartphones, tablets, laptops and more employing them. Indeed it can be hard to imagine what our devices would be like if touch-sensitive screens were never developed. Now researchers at the Georgia Institute of Technology are working on a next generation of touch screens with much greater resolution and sensitivity.

At the heart of this new technology are touch-sensitive transistors called taxels that are made of zinc oxide nanowires. These wires exhibit the piezoelectric effect, which is a linking between electricity and mechanical force. When pressure is applied to a piezoelectric material, an electrical voltage is produced, thereby registering touch. These nanowires however are special because they are also semiconductors, so as pressure is applied to them, their resistance changes. This allows the researchers to achieve much higher sensitivity, comparable to that of human skin, and at a resolution approaching 100 micrometers.

There is still a fair amount of work to do before taxels could enter our devices, including finding a way to produce them from single nanowires instead of bundles and integrating them into CMOS silicon devices. Fortunately the touch-sensitive transistors are already transparent, which is important if they would be placed on our displays.